Biology quiz

1. Which of the following is a possible abbreviation for a genotype?

B. Pp

Rationale: Genotypes are comprised of two of the identical letters (twouppercase, two lowercase, or a combination of the two)

• Which is the best way to determine the phenotype of the feathers on a bird?

B. Look at the bird’s feathers

Rationale: Phenotype refers to the physical aspects. Therefore, the phenotype of the feathers literally denotes the appearance of the feathers.

• Which of the following pairs is not correct?

A. kk = Hybrid

Rationale: A hybrid genotype is represented by 1 capital and 1 lowercase of the same alphabet.

• The genes present in an organism represent the organism’s
• Genotype

Rationale: Genotype is the genetic composition of an organism.

• Which choice represents a possible pair of alleles?

C. K & k

Rationale: Allele refers to two forms of a gene. The above choice demonstrates the two aspects of the same gene (K or k)

• How many alleles for one trait are normally found in the genotype of an organism?
• 2

Rationale: Each parent provides one allele

• Which statement is not true?

B. Phenotype determines genotype

Rationale: The above statement is untrue because, for example, an individual’s skin color can be altered through artificial methods such as plastic surgery.

• Which cross would best illustrate Mendel’s Law of Segregation?

C. Bb × Bb

Rationale: Both parents demonstrate dominant traits. However, the parents will produce some offspring with recessive genes because each parent has a “b”.

• In the cross Yy ×Yy, what percent of offspring would have the same phenotype as the parent?
• 75%

Rationale: In the diagram below, 3 of the 4 outcomes have at least one “Y” producing the dominant phenotype which is similar to the parents.

	Y	y
Y	YY	Yy
y	Yy	yy

In a certain plant, purple flowers are dominant to red flowers. If the cross of the two purple-flowered plants produces some…